We stayed YC concierge this past December and overall, the pre-planning staff was worth every penny that we paid. It sounds like you have that all covered though. Basically, it's a higher level of service and the food/lounge is nice, but hard to imagine that you'd eat $100 worth of food a day there. Aside from a deluxe continental breakfast, it's basically a lot of snack items. In the evenings they do have wine, beer and late night cordials. A nice treat if you plan on spending time at the resort.
What room view type do you have? If you don't have a waterview room booked, that's where I'd put my money instead. Just my .02 cents though.